/*******************************************************************************
 * Copyright (c) 2006 CEA List.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     CEA List - initial API and implementation
 *******************************************************************************/
package com.cea.papyrus.core.ui.dialogs;

import org.eclipse.jface.dialogs.Dialog;
import org.eclipse.jface.dialogs.IDialogConstants;
import org.eclipse.jface.dialogs.IInputValidator;
import org.eclipse.jface.text.source.SourceViewer;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;


// equivalent au inputDialog (code recopie) mais donne un sourceviewer a la place du label
/**
 * 
 */
public class LabelEditorDialog extends Dialog {

    /**
     * The title of the dialog.
     */
    protected String title;

    /**
     * The input value; the empty string by default.
     */
    protected String value = "";//$NON-NLS-1$

    /**
     * The input validator, or <code>null</code> if none.
     */
    protected IInputValidator validator;

    /**
     * Ok button widget.
     */
    protected Button okButton;

    /**
     * Error message label widget.
     */
    protected Text errorMessageText;
    
    /**
     * Error message string.
     */
    protected String errorMessage;
    
    /**
     * SourceViewer : area that displays text.
     */
    protected SourceViewer viewer;

    /**
     * Creates a dialog with OK and Cancel buttons. Note that the dialog
     * will have no visual representation (no widgets) until it is told to open.
     * <p>
     * Note that the <code>open</code> method blocks for input dialogs.
     * </p>
     * 
     * @param dialogTitle the dialog title, or <code>null</code> if none
     * @param validator an input validator, or <code>null</code> if none
     * @param parentShell the parent shell, or <code>null</code> to create a top-level shell
     * @param initialValue the initial input value, or <code>null</code> if none (equivalent to the empty string)
     */
    public LabelEditorDialog(Shell parentShell, String dialogTitle, String initialValue, IInputValidator validator) {
        super(parentShell);
        this.title = dialogTitle;
        if (initialValue == null) {
			value = "";//$NON-NLS-1$
		} else {
			value = initialValue;
		}
        this.validator = validator;
    }

    /*
     * (non-Javadoc) Method declared on Dialog.
     */
    /**
     * 
     * 
     * @param buttonId 
     */
    @Override
	protected void buttonPressed(int buttonId) {
        if (buttonId == IDialogConstants.OK_ID) {
            value = viewer.getDocument().get();
        } else {
            value = null;
        }
        super.buttonPressed(buttonId);
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.window.Window#configureShell(org.eclipse.swt.widgets.Shell)
     */
    /**
     * 
     * 
     * @param shell 
     */
    @Override
	protected void configureShell(Shell shell) {
        super.configureShell(shell);
        if (title != null) {
			shell.setText(title);
		}
    }
 
    /**
     * Returns the ok button.
     * 
     * @return the ok button
     */
    protected Button getOkButton() {
        return okButton;
    }

    /**
     * Returns the text area.
     * 
     * @return the text area
     */
    protected SourceViewer getSourceViewer() {
        return viewer;
    }

    /**
     * Returns the validator.
     * 
     * @return the validator
     */
    protected IInputValidator getValidator() {
        return validator;
    }

    /**
     * Returns the string typed into this input dialog.
     * 
     * @return the input string
     */
    public String getValue() {
        return value;
    }

    /**
     * Validates the input.
     * <p>
     * The default implementation of this framework method delegates the request
     * to the supplied input validator object; if it finds the input invalid,
     * the error message is displayed in the dialog's message line. This hook
     * method is called whenever the text changes in the input field.
     * </p>
     */
    protected void validateInput() {
        String errorMessage = null;
        if (validator != null) {
            errorMessage = validator.isValid(viewer.getDocument().get());
        }
        // Bug 16256: important not to treat "" (blank error) the same as null
        // (no error)
        setErrorMessage(errorMessage);
    }

    /**
     * Sets or clears the error message.
     * If not <code>null</code>, the OK button is disabled.
     * 
     * @param errorMessage the error message, or <code>null</code> to clear
     * 
     * @since 3.0
     */
    public void setErrorMessage(String errorMessage) {
    	this.errorMessage = errorMessage;
    	if ((errorMessageText != null) && !errorMessageText.isDisposed()) {
    		errorMessageText.setText(errorMessage == null ? "" : errorMessage); //$NON-NLS-1$
    		errorMessageText.getParent().update();
    		// Access the ok button by id, in case clients have overridden button creation.
    		// See https://bugs.eclipse.org/bugs/show_bug.cgi?id=113643
    		Control button = getButton(IDialogConstants.OK_ID);
    		if (button != null) {
    			button.setEnabled(errorMessage == null);
    		}
    	}
    }
	
}
